In the can container typified by a beverage can filled with liquid contents, the can end including a pull-tab that easily open the can is frequently used as the easy-open mechanism. FIG. 1 is a front view illustrating an example of the easy-open can end including the pull-tab, and FIG. 2 is a longitudinal sectional view of the easy-open can end. A pull-tab 7 is attached to a can end 1 by a rivet 5. When a tab tail 15 of the pull-tab 7 is pulled up while caught with a finger, the neighborhood of the rivet 5 is bent to become a fulcrum, and a leading end of a nose portion 13 of the pull-tab 7 becomes a point of action to push down a score panel 19 that is of a portion surrounded by a score 17 (notch line for guiding rip-opening of can end) in a surface of a panel 3. As a result, the surface of the panel 3 is rip-opened along a shape of the score 17, and the score panel 19 is pressed into the can without leaving from a can end 1 to open the can. At this point, because a faucet is opened, “can opening” is called “opening”.
In the easy-open can end, at the beginning of a can opening operation, it is typical to insert a finger into a gap between the panel 3 and the tab tail 15 of the pull-tab 7 to pull up the pull-tab 7. At the beginning of the can opening operation, it is typical that the pull-tab 7 be pulled up with a large force in order to initially rupture the score 17. Therefore, it is preferable to improve ease of catching of the pull-tab 7 with a finger (hereinafter also referred to as “finger catching property (finger access)”) in order to enhance a can opening property. Conventionally, as illustrated in FIGS. 1 and 2, in order to improve the finger catching property, a recess called a finger deboss 21 is provided in the panel 3 near the tab tail 15 of the pull-tab 7 such that the finger goes around to the under side of the tab tail 15. However, the finger catching property is insufficiently improved, because the finger deboss 21 cannot sufficiently largely be formed according to a finger size from the viewpoints of restriction of a surface space of the panel 3 and preservation of the strength of the can end. Therefore, there have been proposed following methods in order to improve the finger catching property.
That is, the method in which projection is provided in an upper surface of the panel 3, which is in contact with a lower surface of the pull-tab 7, and the method for previously bending the pull-tab 7 are described as the method for uplifting the tab tail 15 from the panel 3 only by a necessary amount in order to spread a gap between the tab tail 15 of the pull-tab 7 and the panel 3 to easily catch the tab tail 15 with the finger (for example, see Japanese Utility Model Publication No. 8-6746). There has also been proposed a method for easily catching the tab tail 15 with the finger by previously providing the a low-strength portion in an outer rim 11 (outside portion of a U-shape notch portion 9 of the pull-tab) of the pull-tab 7 such that the pull-tab 7 is bent by a predetermined amount with a small force to lift the tab tail 15 at the beginning of the can opening operation (for example, see Japanese Utility Model Publication Laid-Open No. 3-111939).